Positive retraction honing tool



Dec. 15, 1942. J. B. KLEIN 2,304,930

POSITIVE RETRACTION HONING TOOL Filed April 1, 1938 INVENTOR. [I JAMES B. KLE|N ATTORNEY.

Patented Dec'. 1s, 1942 UNITE-D vs'rATlas Y PATENT OFFICE 'A POSITIVE nnrnzf'risos; noNmG Tool.

James B. Klein, Detroit, Mich.,

assignments, to Micromatic Detroit, Mich., a corporation asslgnor, by mesne Bone Corporation,

of Michigan v Application April l, 1938, Serial No. 199,475

7 Claims.

'I'his invention relates to cylinder hones. More specifically, it relates to a cylinder honing tool wherein the abrasive stones are positively retracted by mechanical means when it is desired to insert the tool into or withdraw it from the bore of the workpiece.

When honing cylindrical bores, it is necessary that the abrasive members of the honing tool be retracted in a radial direction relative to the axis of the tool so that the tool may be inserted into the bore. After insertion of the tool into the bore, the abrasive stones are expanded radially outwardly, by cam means, so that they contact the wall of the bore, and the tool is simultaneously rotated and reciprocated until the desired amount of metal is removed. Ihe abrasive stones are then retracted so that the tool may be withdrawn from the bore without damage thereto.

It has heretofore been the practice in the art to affect the retraction of the stones by spring means. Both flat and round springs have been used. Attention is directed to the U. S. Patents Numbers 1,610,681 and 1,978,428 for examples of this construction.

Due to the high honing speeds now employed in production honing, considerable difficulty has been experienced in removing the tools from the bore dueto the fact that the friction between the stone holders and the sides of the radial supporting wings of the tool body has prevented the stones from responding to the influence of the retracting springs after the expanding cones have been withdrawn.

As a result of this, the workpiece bore is frequently damaged by the stones as they are withdrawn.

The present invention overcomes this dimculw by providing a positive means for moving the stones radially inwardly when it is desired to withdraw the tool from the workpiece.

Cil

Reference is made .to the accompanying drawl ing which illustrates several of the many forms in which the invention may be embodied.

Fig. 1 is an elevation, partly in section, of one I form of the inventio Fig. 2 is a section along line II-II of Fig. 1. Fig. 3 is an elevation, partly in section, of a modification.

Figs. 4 and 5 are side and end views respectively of one of the adjusting members of the tool shown in Fig. 1.

Figs. 6 and '7 are side and end views respectively of one of the adjusting members of the tool shown in Fig. 3.

Referring to Fig. 1, the body of the tool is indicated at I Il and this body is provided with a plurality of radially extending wings I I, illustrated in Fig. 2. Two series of slots are provided between the radial wings; one series carrying the abrasive members I2, and the other series carrying the non-abrading guide members I3. These guide members are for the purpose 0f guiding the tool during the period that it is being inserted into and withdrawn from the workpiece, and are fully described in copending application, Serial No. 103,656, led October 2, 1936, and which matured as Patent No. 2,263,781 November 25, 1941. These guides are adjustable by means of the axially slidable adjusting member Il, the ring member I5 and the adjusting collar I6. By rotating the adjusting collar I6, the ring member I5 may be moved axially of the tool lbecause of the threaded connection between the two members. This causes an axial movement of the adjusting member I4 thereby eiecting radial movement of the guides I3 because of the action of the cooperating inclined surfaces I1. Garter springs 30 are provided to retain the guides in assembled relation, and to move them radially inwardly when it is desired to decrease the adjusted diameter of the tool.

The abrasive members I2 are likewise mounted for. radial movement relative to the body of the tool. Each abrasive stone I2 is mounted on a holder i8. The holder I8 is positioned in a slot I9 between the radial wings Il (see Fig. 2). The lower portion I8a of the stone holder is narrower than the main body portion thereof and this engges the slot 20 which is cut into the tool body A T-shaped projection 2| is provided on the stone holder as shown in Figs. l and 2. This projection has a pair of oppositely inclined surfaces 22 and 23 which engage in complementary T-shaped slots in the annularly shaped ends 24-25 of the adjusting cone members '2G-21. One of the cone adjusting members is shown in detail in Figs. 4 and 5.

An adjusting shaft 28 extends through the tool drive shaft 29, as shown in Fig. 1. The lower cone member 26 is threaded on the end of shaft 28 and the upper cone member 21 is loose on said shaft. A coil spring 39 is provided to urge the cone members apart. As is obvious from the drawing, if the shaft 28 is rotated, the cone members may be moved toward or away from each other as desired. The lower and upper cones are prevented. from turning by the pins 3| in the body III.

The portion I8a of the stone holder has beveled projections at its ends which engage the upper and lower cones as shown in Fig. 1. When the cones are brought closer together, under the iniiuence of the shaft 28, the stone holders will 5 be moved radially outwardly. On the other hand, when the cones are moved away from each other, the stone holders are positively moved radially inwardly because of the engagement of the T-shaped projections 2| with the T slots in the annular members 24-25.

Garter springs 38 are provided for convenience in assembling the tool, but may be omitted if desired.

Referring now to the form of the invention 15 shown in Fig. 3, the tool illustrated therein differs from that shown in Fig. 1 in that it is of the one way cone type. That is, the stone actuating members 26'21 are moved in the same direction when the stones are adjusted, instead of in opposite directions, as is the casein the tool illustrated in Fig. 1.

The wiper adjusting mechanism of the modified form of tool is identical to that shown in Fig. 1 and the description thereof will be omitted for the sake of brevity,

4The stone adjusting members 26' and 21 arev rigidly mounted on the adjusting shaft 28' which is retained in the lower end of the shaft 32 by a threaded connection. The shaft 28' is rel strained from rotational movement by the key 33, but is capable of axial movement.

The stoneholders i8 are similar to the stoneholders I8, except that the T-shaped projections 22-23 are inclined in the same direction and are positioned at opposite ends of the holder.

'I'he tool shown in Fig. 3 operates as follows: by rotating the shaft`32 in one direction, the shaft 28 will be drawn upwardly and the stoneholders i8' will be forced radially outwardly thereby expanding the diameter of the tool. Conversely, when the shaft 32 is rotated in an opposite direction, shaft 28 will be forced downwardly and the stoneholders i8 will be positively drawn inwardly thereby contracting the diameter of the tool.

If desired, instead of rotating shaft 32 to adjust the position of the honing stones, the shaft may be bodily moved axially of the tool. In practice, both methods of adjusting the tool are frequently used in the same honing set-up. Mechanism is provided for rotating shaft 32 so that the maximum and/or minimum diameters of the tool may be accurately fixed, and a separate mechanism is provided to move shaft 32 axially 55 0f the tool for the purpose of effecting a quick acting contraction and expansion of the tool when it is desired to insert it into the bore of the workpiece or withdraw it therefrom. This type of tool is especially advantageous for use with a multiple honing set-up of the automatic type such as that shown in the copending application of Frank Jeschke, Serial No. 162,566, led September 4, 1937, and which matured as Patent No. 2,277,985, March 31, 1942.

I claim:

1. A grinding device comprising a working head having a central bore and radial slots, grinding devices supported in some of the slots, guide ele, 70 ments carried by other of the slots, an adjustiment mechanism in the central bore for positive'- ly moving the grinding elements outwardly and inwardly, and means separate from said adjust ment mechanism for positioning said guide ele- 75 ments independently of the movement of said guiding elements.

2. A honing tool comprising a supporting head having a longitudinal central bore and circumferentially spaced radial slots, abrasive elements supported in some of the slots, guide elements supported in other of the slots, adjustment means in the central bore for positively moving said abrasive elements outwardly and inwardly, a plurality of longitudinally movable members one of which is associated with each of said guide elements, separate adjusting means independent of said first means for shifting said longitudinally movable members to radially position said guide elements.

3. A cylinder grinding device comprising, in combination, a rotatable supporting head having a series of radially extending slots arranged at circumferentially spaced intervals, at least three guide elements supported respectivelyin three of the slots which are annularly displaced with respect to each other at substantially equal circumferentially spaced intervals, movable members, one of said members being associated with and adapted to engage each of said guide elements,

adjustment means adapted upon operation thereof to simultaneously actuate all of said'members to move said guide elements in a radial direction only, abrasive elements supported by the remaining slots, and other adjustment means inde- .pendent of said rst adjusting means for positively moving said abrasive elements outwardly and inwardly in a radial direction independently of the movement of said guideelements.

4. A cylinder grinding device comprising, in combination, a rotatable head, a plurality of mounts supported by saidV head at circumferentially spaced intervals, three guide elements supported respectively in three of the mounts which are annularly displaced with respect to each other by substantially 120 degrees, three longitudinally movable members, one of said members being associated with and adapted to engage each mount carrying a guide element, adjustment means for actuating all of said members to move said guide elements, abrasive elements supported by the remaining mounts, and other adjustment means indepe dent of said rst adjustment means for positively moving said abrasive elements outwardly and inwardly independently of the position or ,movement of said guide elements.

5. A tool for honing cylindrical bores comprising a head having a central longitudinal bore, a plurality of abrasive stonesr supported on the outer circumference of said head with the working faces upon the circumference of a. cylinder, a unit cam element disposed in said bore having a. pair of like cam surfaces projecting in the same direction, a shaft screw threaded to said unit and mounted for longitudinal movement whereby uponl rotation of said shaft the cam unit is slowly moved and upon longitudinal movement ofthe shaft the cam unit is moved at a faster rate for expanding said abrasive stones while maintaining their faces on'the circumference of acylinder.

6. A honing tool having a head in which a plurality of abrasive stones are mounted for radial movement while being maintained on the circumference of a cylinder, a pair of spaced cams iixed as a unit for moving said abrasive stones radially, a shaft having screw threaded engagement withsaid cam unit for moving said cam unit longitudinally when the shaft is moved longitudlnaliy ald also when rotated relative to said' unit.

ment with said cam unit for moving said cam unit longitudinally unit. and means for the cams when the sha mittins said cams to mo when the shaft is moved 1ongitudinally and also when rotated relative to said preventing the rotation of ft is rotated while perve longitudinally.

JAMES B. KLEIN. 

